The present invention is directed to napkin dispensers generally, and more particularly to a dispenser for receiving interfolded napkins and dispensing them while reducing the tendency of the napkins to curl about an edge thereof.
Spring biased napkin dispensers are well known in the art. An early example appears in U.S. Pat. No. 1,682,580 to Pratt. In the ""580 patent there is provided a napkin dispenser including a casing and a pressure carriage to urge the stack of napkins towards the face or dispensing plate. In U.S. Pat. No. 1,930,805 to Hope there is disclosed a napkin dispenser including a container adapted to receive a stack of napkins which are urged toward the dispensing aperture by way of a follower attached to a leaf spring. Still yet another example of a napkin dispenser appears in U.S. Pat. No. 1,993,885 to Horwilt. The device of the ""885 patent includes a face plate that is outwardly bulged or obliquely offset to afford a pocket like extension of progressively increasing depth from the bottom to the top which arrangement defines a transverse slot of relatively small width.
In U.S. Pat. No. 2,426,136 to Agamaite, Jr. there is disclosed a napkin dispenser having a lid which may be opened for replenishing the napkins and a latch controlled by the lid to hold a follower in retracted position while the napkins are being replenished.
U.S. Pat. No. 2,852,158 to Jones et al. discloses a napkin dispenser provided with a pair of spaced pusher plates attached to the free ends of a U-shaped spring which urges napkins towards a dispensing aperture.
Of more recent vintage is U.S. Pat. No. 4,329,001 to Filipowicz et al wherein there is disclosed a dispenser for folded paper napkins including a cabinet with a carriage assembly. A pair of constant force springs are affixed to the cabinet and engage the rear of the pressure plate to urge the plate and carriage assembly forwardly against the rear of the napkin supply to facilitate individual removal of the napkins through the cabinet opening.
In U.S. Pat. No. 4,679,703 to De Luca there is disclosed a napkin dispenser including means for preventing napkins from bunching at the dispensing opening. A pair of pressure relief rods are provided along the upper and lower portions of the dispenser face plate to relieve pressure between the face plate and the center portion of the napkin stack. According to the ""703 patent the friction between each napkin is substantially reduced thereby permitting individual napkins to be withdrawn from the dispenser without displacing napkins remaining in the stack.
U.S. Pat. No. 4,838,454 to Salzmann et al. discloses a napkin dispenser including a drawer which slides in and out of a housing and a push plate which also slides in the housing and a spring to the push napkins forward. A pair of locks on the rear of the drawer in the napkin dispenser push the plate forward when the drawer is open but pivot to release the push plate when the drawer is closed so that the napkins are not pressed too tightly, even if napkins are overloaded into the drawer when it is open.
U.S. Pat. No. 5,076,466 to Petterson et al. shows a napkin dispenser with anti-overfill mechanism. Generally speaking the dispenser includes a housing, a support member movably mounted within the housing and a follower for urging the stack in the direction of a dispenser element included in the support member. The apparatus includes a mechanism for engaging the follower and retaining it at a predetermined location relative to the support member when the support member is in open condition which is disengaged in the follower when the support member moves to its closed position to compensate for any over filling of the dispenser.
The foregoing patents (the disclosures of which are incorporated herein by reference) may be distinguished from gravity feed devices of the class generally employed to dispense heavier weight paper towels for example, as are shown in U.S. Pat. No. 5,950,863 to Schutz et al. by virtue of the fact that a spring biased device operates quite differently than a gravity feed device and does not rely primarily on the weight of the stack for delivery of product to the dispensing aperture.
In existing dispensers for napkins, when an interfolded napkin is dispensed it is often found that a tightly curled portion is formed at one end of the napkin in every other napkin in a stack of single fold napkins, particularly when the napkin is dispensed through a slot located away from the centerline of the napkin stack. This curl not only hinders proper use of the napkin by reducing the napkin""s overall size, but is also aesthetically unattractive. It has been discovered in accordance with the present invention that this curl is induced in the napkin during the dispensing operation by interaction between napkins in the stack with each other and the dispenser. This phenomenon seems to be somewhat more pronounced when baffles are used to limit the ease of withdrawal of multiple napkins. The invention which is described in detail hereinafter is directed to reducing and most preferably substantially eliminating the curl associated with dispensing a stack of interfolded napkins. Other advantages of the invention include promoting the distribution of a single napkin at a time and controlling the tendency of napkins to bunch about the dispensing slot or aperture.
A curl reducing adapter kit is provided for a napkin dispenser used for dispensing interfolded napkins. The dispenser generally includes an enclosure provided with a dispensing wall defining a horizontal dispensing slot about its upper portion and a slidably mounted, biased pressure carriage adapted to advance a stack of napkins in the enclosure toward the dispensing wall. The kit includes a tongue for mounting about the dispensing wall such that the tongue projects into the dispensing slot and narrows the slot, about its central portion in one preferred embodiment. The tongue includes a plurality of friction tabs configured to project inwardly into the enclosure from the upper inner lip of the modified dispensing slot and frictionally engage the napkins to limit bulge through the slot. A plurality of orienting ridges configured to be disposed about a lower portion of the dispensing wall adapted to frictionally engage the napkin stack are provided to guide napkins toward the dispensing aperture and reduce curl. A plurality of curl limiting tabs configured to be disposed about the lower inner lip of the dispensing slot also project inwardly into the enclosure so as to frictionally engage the stack of napkins and further discourage curl. In a typical embodiment, there is further provided a pressure plate for mounting on the pressure carriage in opposed facing relationship to the dispensing wall, the pressure plate having a pressure rib on its upper portion which is configured to project towards the dispensing wall closer than the lower portion of the pressure plate in opposed facing relationship to said dispensing wall. In such embodiments, the pressure rib of the pressure plate is configured to project a distance of from about xc2xd inch to about 1 inch closer to the dispensing wall then the lower surface of the pressure plate in opposed facing relationship to the dispensing wall. The kit also limits the number of napkins which can be dispensed in a single grasping motion.
In one embodiment, the tongue is preferably configured to define a narrow elongated slit about the central portion of the dispensing slot as well as to define a pair of open areas about the terminal portions thereof. Typically, the terminal portions have an open area span of at least about xc2xd inch and more characteristically, the terminal portions have an open area span of at least about ⅓ inch or sometimes at least about 1 inch. If so desired, the tongue can be configured to define an open area in the central region of the dispensing aperture. The narrowed portions of the dispensing slot generally spans more than about 50 percent of the transverse dimension of an interfolded napkin being dispensed therethrough and usually spans more than about 70 percent of the transverse dimension of an interfolded napkin being dispensed therethrough. The tongue is generally configured to define the narrow portion of the dispensing slot to have an opening width of from about {fraction (1/16)} inch to about xe2x85x9e inch whereas an opening width of from about xe2x85x9 inch to about xe2x85x9e inch is more typical and an opening width about the narrow portion of the dispensing slot of from about xe2x85x9c inch to about ⅝ inch is preferred.
In a preferred embodiment, the plurality of friction tabs on the tongue are generally semicircular disc-shaped (half circular) and have a diameter of from about xc2xc inch to about xc2xd inch. The plurality of friction tabs on the tongue may include from about 6 to about 10 friction tabs and typically have a friction surface width of from about {fraction (1/16)} inch to about xc2xc inch.
The plurality of orienting ridges may include or consist of a plurality of triangular-shaped ribs which project progressively further into said enclosure toward the base of said dispensing wall as is shown in the drawings which are appended. The triangular orienting ridges usually project inwardly into the enclosure at their base a distance of from about xc2xc inch to about 1 inch and have a friction surface of a width of from about {fraction (1/16)} inch to about xc2xc inch. While any suitable number of orienting ridges may be employed, about 4 to about 8 orienting ridges configured to be disposed about the lower portion of the dispensing wall is typical.
As noted above, the adapter kit further includes curl limiting tabs about the lower inner lip of the dispensing slot which are generally semicircular disc-shaped tabs in a preferred embodiment and have a diameter of from about xc2xc inch to about xc2xd inch. From about 8 to about 12 curl limiting tabs is typical. These tabs may also have a friction surface width of from about {fraction (1/16)} inch to about xc2xc inch.
In another aspect of the invention, there is provided a napkin dispenser for dispensing a stack of interfolded napkins while reducing curling along edges thereof comprising an enclosure with a dispensing wall having upper and lower portions provided with an elongated dispensing aperture extending across the dispensing wall between the upper and lower portions thereof, the dispensing wall being further provided with a pressure exerting member projecting inwardly into the interior of the enclosure along an edge portion of one of the upper and lower portions of the dispensing wall. The napkin dispenser is further provided with a pressure carriage slidably mounted in the enclosure having a pressure plate in an opposed facing relationship to the dispensing wall, the pressure plate of the pressure carriage being provided with a pressure rib opposing the portion of the dispensing wall distal to the pressure exerting member of the dispensing wall. Biasing means such as a spring urge the pressure carriage towards the dispensing wall. The enclosure and pressure carriage are configured to receive a stack of interfolded napkins between the dispensing wall and the pressure plate of the pressure carriage, such that the napkins are engaged by the pressure exerting member of the dispensing wall and the pressure rib of the pressure plate and wherein the biasing means are operative to advance the stack of napkins toward the dispensing wall as napkins are withdrawn from the dispenser. So also, undesirable dispensing of multiple napkins in a single grasping motion is inhibited from the dispenser of the present invention.
In yet another aspect of the invention, there is provided a napkin dispenser for dispensing a stack of interfolded napkins while reducing curling along the edges thereof comprising: an enclosure with a dispensing wall provided with an elongated dispensing aperture extending across the dispensing wall dividing it into upper and lower portions, wherein the lower portion of the dispensing wall is larger than the upper portion of the dispensing wall and is further provided with a plurality of pressure exerting ribs extending inwardly into the enclosure from the lower portion of the dispensing wall, as well as a plurality of friction tabs about the upper edge of the dispensing aperture and a plurality of curl limiting tabs about the lower edge of the dispensing aperture, the tabs extending generally inwardly into the enclosure. A pressure carriage is slidably mounted in the enclosure and has a pressure plate in an opposed facing relationship to the dispensing wall, the pressure plate being provided with an upper pressure rib in opposed facing relationship to the upper portion of the dispensing wall and a lower portion in opposed facing relationship to the lower portion of the dispensing wall; and biasing means for urging the pressure carriage towards the dispensing wall. The enclosure and the pressure carriage are configured to receive the stack of interfolded napkins between the dispensing wall and the pressure plate of the pressure carriage such that the napkins are engaged by the plurality of pressure exerting ribs of the dispensing wall, the plurality of friction tabs and curl limiting tabs of the dispensing wall and the pressure rib of the pressure carriage and wherein the biasing means operate to advance the stack of interfolded napkins toward the dispensing wall as napkins are withdrawn from the dispensing aperture.
In a still yet further aspect of the invention there is provided a napkin dispenser for dispensing a stack of interfolded napkins including: an enclosure including a dispensing wall defining generally a narrow elongated dispensing aperture with at least one open area over a portion of the dispensing aperture; a pressure carriage slidably mounted in the enclosure provided with a pressure plate in opposed facing relationship to the dispensing wall; a plurality of friction tabs about the first inner lip of the dispensing aperture projecting inwardly into the enclosure towards the pressure plate of the pressure carriage for engaging the napkins; a plurality of curl limiting tabs about the second inner lip of the dispensing aperture projecting inwardly into the enclosure towards the pressure plate of the pressure carriage for engaging the napkins; and biasing means for urging the pressure carriage towards the dispensing wall. The enclosure, pressure carriage and dispensing wall are thereby adapted and configured to receive a stack of interfolded napkins between the pressure plate of the pressure carriage and the dispensing wall and advance the stack towards the dispensing wall as the napkins are withdrawn from the dispenser. The inventive adapter and dispensers so configured are especially suitable for dispensing a stack of single fold napkins one at a time or seriatim.